What is cold backup and hot backup in Oracle : Advantage Disadvantage Explained : RDBMS FAQ

 

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What is cold backup and hot backup ?

1. Cold Backup: It is copying the three sets of files (database files, redo logs, and control file) when the instance is shut down. This is a straight file copy, usually from the disk directly to tape. You must shut down the instance to guarantee a consistent copy. If a cold backup is performed, the only option available in the event of data file loss is restoring all the files from the latest backup. All work performed on the database since the last backup is lost. 

2. Hot Backup: Some sites (such as worldwide airline reservations systems) cannot shut down the database while making a backup copy of the files. The cold backup is not an available option.

What is meant by Proactive, Retroactive and Simultaneous Update.

1. Proactive Update: The updates that are applied to database before it becomes effective in real world.

2. Retroactive Update: The updates that are applied to database after it becomes effective in real world.

3. Simultaneous Update: The updates that are applied to database at the same time when it becomes effective in real world.

 What is Storage Manager?

It is a program module that provides the interface between the low-level data stored in database, application programs and queries submitted to the system.

 What is Buffer Manager?

It is a program module, which is responsible for fetching data from disk storage into main memory and deciding what data to be cache in memory.

 What is Transaction Manager?

It is a program module, which ensures that database, remains in a consistent state despite system failures and concurrent transaction execution proceeds without conflicting.

What is File Manager?

I

t is a program module, which manages the allocation of space on disk storage and data structure used to represent information stored on a disk.

What is Authorization and Integrity manager?

It is the program module, which tests for the satisfaction of integrity constraint and checks the authority of user to access data.

আসাম সরকারী চাকরির শূন্যপদে অনলাইনে আবেদন করুন: The Assam Direct Recruitment Commission

 আসাম সরকারী চাকরির শূন্যপদে অনলাইনে আবেদন করুন: আসাম সরাসরি নিয়োগ কমিশন 

The Assam Direct Recruitment Commission , Assam Government Job Vacancy Recruitment Online Process. 

 আসাম ডাইরেক্ট রিক্রুটমেন্ট কমিশন